Invite systems often place the application developer's and user's interests at odds. Most existing mobile invite systems simply present potential invitees alphabetically. Below are summarized approaches from some well-known existing companies:
Path: (email addresses sorted alphabetically)
Zynga (in their hit Running with Friends game, contacts sorted by activity or alphabetically)
Fancy: (current users first, then sorted alphabetically)
Facebook: (sorted by mutual friend count)
Current systems do not apply feedback loops to inform the ranking of potential invitees, as it appears that their sorting is purely one dimensional (alphabetical or activity-based or mutual friend count).